More robustly bound the root

Author: Chrismarsh

src/modules/Harder_precip_phase.cpp

@@ -113,8 +113,10 @@ void Harder_precip_phase::run(mesh_elem& face)
     };
 
     double guess = T;
-    double min = -50;
-    double max = 50;
+    // Ensure these cover more than the range of plausible.
+    // It's just to ensure the root is bounded.
+    double min = -100;
+    double max = 100;
     double digits = 6;
 
     double Ti = 0;
@@ -127,16 +129,6 @@ void Harder_precip_phase::run(mesh_elem& face)
     {
         SPDLOG_ERROR("Ta={}, RH={}, ea={}, guess={}, min={}, max={}",
             Ta, RH, ea, guess, min, max);
-        try
-        {
-            // try again but instrument it this time to see what went wrong
-#define BOOST_MATH_INSTRUMENT
-            Ti = boost::math::tools::newton_raphson_iterate(fx, guess, min, max, digits);
-#undef BOOST_MATH_INSTRUMENT
-        }
-        catch(...)
-        {
-        }
         CHM_THROW_EXCEPTION(module_error, "Harder_precip_phase newton_raphson_iterate failed to converge");
     }